Ratchford Elizabeth V, Salameh Maya J, Morrissey Nicholas J
Vascular Medicine, Division of Cardiology, Department of Medicine, Johns Hopkins University School of Medicine, Baltimore, MD, USA.
Vascular. 2009 Jan-Feb;17(1):51-4. doi: 10.2310/6670.2008.00069.
Bradycardia may lead to an underestimation of carotid stenosis by duplex ultrasonography. An 83-year-old man with asymptomatic bradycardia was referred to our institution after magnetic resonance angiography revealed greater than 90% stenosis of the proximal left internal carotid artery (ICA). Two separate carotid duplex examinations were subsequently performed at different vascular laboratories within our institution. Both studies showed elevated (but borderline for the highest category of stenosis) peak systolic velocities with relatively low end-diastolic velocities (EDVs). Angiography demonstrated more than 90% stenosis of the left ICA. Carotid endarterectomy was then performed. In conclusion, interpreting physicians and vascular ultrasound technologists should be aware of the spurious decrease in EDV that accompanies bradycardia. Further imaging may be warranted when revascularization is a consideration for bradycardic patients with borderline results on carotid duplex ultrasonography.
心动过缓可能导致双功超声检查低估颈动脉狭窄程度。一名83岁无症状心动过缓男性在磁共振血管造影显示左侧颈内动脉（ICA）近端狭窄超过90%后被转诊至我院。随后在我院不同的血管实验室进行了两次独立的颈动脉双功超声检查。两项研究均显示收缩期峰值流速升高（但处于最高狭窄类别临界值），舒张末期流速（EDV）相对较低。血管造影显示左侧ICA狭窄超过90%。随后进行了颈动脉内膜切除术。总之，解读医生和血管超声技师应意识到心动过缓伴随的EDV假性降低。对于颈动脉双功超声检查结果处于临界值的心动过缓患者，若考虑血管重建，则可能需要进一步影像学检查。
